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Zhang Z, Zhou M, Liu J, Li J, Yang J, Chang H. Preparation and characterization of cornstalk microspheric hydrochar and adsorption mechanism of mesotrione. ROYAL SOCIETY OPEN SCIENCE 2021; 8:202209. [PMID: 34234952 PMCID: PMC8242927 DOI: 10.1098/rsos.202209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 05/26/2021] [Indexed: 06/13/2023]
Abstract
In this study, cornstalk was pyrolysed to obtain hydrochar (HC), which was used to remove mesotrione from aqueous solutions. HC characterization and batch experiments were conducted to investigate mesotrione adsorption and the underlying mechanism. The characterization revealed microspheres on the HC surface. FT-IR spectra showed that the HC contained a large number of -OH groups, C=C bonds of aromatic rings, C-H groups in aromatic rings and phenolic C-O bonds. The adsorption results showed that the mesotrione adsorption ability gradually increased as the HC preparation temperature increased. The quasi-second-order kinetic equation (R2 ≥ 0.9860, p < 0.05) agreed well with the mesotrione adsorption process. The maximum monolayer adsorption capacity, which was obtained at pH 7 and 45°C with HC prepared at 240°C, was 3181.7 mg kg-1 with the Langmuir isotherm model (R2 ≥ 0.9491, p < 0.05). Van der Waals and dipole forces and hydrogen bonds were inferred as the main adsorption mechanisms. HC has potential as an effective and energy-saving adsorbent for mesotrione to reduce environmental pollution.
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Affiliation(s)
- Zhongqing Zhang
- College of Resources and Environmental Science, Jilin Agricultural University, Changchun 130118, Jilin, People's Republic of China
| | - Mengmeng Zhou
- College of Resources and Environmental Science, Jilin Agricultural University, Changchun 130118, Jilin, People's Republic of China
| | - Jinhua Liu
- College of Resources and Environmental Science, Jilin Agricultural University, Changchun 130118, Jilin, People's Republic of China
| | - Jiahao Li
- College of Resources and Environmental Science, Jilin Agricultural University, Changchun 130118, Jilin, People's Republic of China
| | - Jingmin Yang
- College of Resources and Environmental Science, Jilin Agricultural University, Changchun 130118, Jilin, People's Republic of China
| | - Haibo Chang
- College of Resources and Environmental Science, Jilin Agricultural University, Changchun 130118, Jilin, People's Republic of China
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Pergal MV, Kodranov ID, Pergal MM, Avdin VV, Manojlović DD. Oxidative degradation and mineralization of bentazone from water. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2020; 55:1069-1079. [PMID: 32880524 DOI: 10.1080/03601234.2020.1816091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Bentazone degradation efficiency and mineralization in water solutions using chlorine dioxide treatment were evaluated. Double distilled water and a river water sample spiked with bentazone were studied and compared after chlorine dioxide treatment. Degradation efficiency was determined using high-performance liquid chromatography (HPLC). Daphnia magna toxicity testing and total organic carbon (TOC) analysis were used to ascertain the toxicity of the degraded solutions and mineralization degree. Bentazone degradation products were identified using gas chromatography with a triple quadrupole mass detector (GC-MS-MS). A simple mechanistic scheme for oxidative degradation of bentazone was proposed based on the degradation products that were identified. Decrease in D. magna mortality, high degradation efficiency and partial bentazone mineralization were achieved by waters containing bentazone degradation products, which indicate the formation of less toxic compounds than the parent bentazone and effective removal of bentazone from the waters. Bentazone degraded into four main degradation products. Humic acid from Sava River water influenced bentazone degradation, resulting in a lower degradation efficiency in this matrix (about 10% lower than in distilled water). Chlorine dioxide treatment of water to degrade bentazone is efficient and offers a novel approach in the development of new technology for removal of this herbicide from contaminated water.
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Affiliation(s)
- Marija V Pergal
- Institute of Chemistry, Technology and Metallurgy, National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Igor D Kodranov
- Faculty of Chemistry, University of Belgrade, Belgrade, Serbia
| | | | - Viacheslav V Avdin
- Faculty of Chemistry, Institute of Natural and Exact Sciences, South Ural State University, Chelyabinsk, Russia
| | - Dragan D Manojlović
- Faculty of Chemistry, University of Belgrade, Belgrade, Serbia
- Faculty of Chemistry, Institute of Natural and Exact Sciences, South Ural State University, Chelyabinsk, Russia
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Šojić Merkulov D, Lazarević M, Djordjevic A, Náfrádi M, Alapi T, Putnik P, Rakočević Z, Novaković M, Miljević B, Bognár S, Abramović B. Potential of TiO 2 with Various Au Nanoparticles for Catalyzing Mesotrione Removal from Wastewaters under Sunlight. NANOMATERIALS 2020; 10:nano10081591. [PMID: 32823509 PMCID: PMC7466515 DOI: 10.3390/nano10081591] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 08/04/2020] [Accepted: 08/06/2020] [Indexed: 11/25/2022]
Abstract
Nowadays, great focus is given to the contamination of surface and groundwater because of the extensive usage of pesticides in agriculture. The improvements of commercial catalyst TiO2 activity using different Au nanoparticles were investigated for mesotrione photocatalytic degradation under simulated sunlight. The selected system was 2.43 × 10−3% Au–S–CH2–CH2–OH/TiO2 (0.5 g/L) that was studied by transmission electron microscopy and ultraviolet-visible (UV-Vis) spectroscopy. It was found that TiO2 particles size was ~20 nm and ~50 nm, respectively. The Au nanoparticles were below 10 nm and were well distributed within the framework of TiO2. For 2.43 × 10−3% Au–S–CH2–CH2–OH/TiO2 (0.5 g/L), band gap energy was 2.45 eV. In comparison to the pure TiO2, addition of Au nanoparticles generally enhanced photocatalytic removal of mesotrione. By examining the degree of mineralization, it was found that 2.43 × 10−3% Au–S–CH2–CH2–OH/TiO2 (0.5 g/L) system was the most efficient for the removal of the mesotrione and intermediates. The effect of tert-butanol, NaF and ethylenediaminetetraacetic acid disodium salt on the transformation rate suggested that the relative contribution of various reactive species changed in following order: h+ > ●OHads > ●OHbulk. Finally, several intermediates that were formed during the photocatalytic treatment of mesotrione were identified.
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Affiliation(s)
- Daniela Šojić Merkulov
- Department of Chemistry, Biochemistry and Environmental Protection, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia
| | - Marina Lazarević
- Department of Chemistry, Biochemistry and Environmental Protection, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia
| | - Aleksandar Djordjevic
- Department of Chemistry, Biochemistry and Environmental Protection, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia
| | - Máté Náfrádi
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary
| | - Tünde Alapi
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary
| | - Predrag Putnik
- Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia
| | - Zlatko Rakočević
- Institute for Nuclear Sciences "Vinča", University of Belgrade, Mihajla Petrovića Alasa 12-14, 11351 Vinča, Belgrade, Serbia
| | - Mirjana Novaković
- Institute for Nuclear Sciences "Vinča", University of Belgrade, Mihajla Petrovića Alasa 12-14, 11351 Vinča, Belgrade, Serbia
| | - Bojan Miljević
- Faculty of Technology, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia
| | - Szabolcs Bognár
- Department of Chemistry, Biochemistry and Environmental Protection, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia
| | - Biljana Abramović
- Department of Chemistry, Biochemistry and Environmental Protection, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia
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Gomes LM, Silva JM, Duarte JLS, Tavares MG, Santos EL, Machado SS, Tonholo J, P. S. Zanta CL. Ecotoxicological evaluation of a fish farming effluent treated by Fenton oxidation and coagulation process. SEP SCI TECHNOL 2019. [DOI: 10.1080/01496395.2019.1662808] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Lúcio M. Gomes
- Tabuleiro do Martins, Institute of Federal University of Alagoas, Maceió-AL, Brazil
| | - Jaqueline M. Silva
- Tabuleiro do Martins, Institute of Federal University of Alagoas, Maceió-AL, Brazil
| | - José L. S. Duarte
- Tabuleiro do Martins, Institute of Federal University of Alagoas, Maceió-AL, Brazil
- Laboratorio de Processos (LaPro), Centro de Tecnologia, Universidade Federal de Alagoas, Maceió, AL, Brasil
| | - Mariana G. Tavares
- Tabuleiro do Martins, Institute of Federal University of Alagoas, Maceió-AL, Brazil
| | - Elton L. Santos
- Agricultural Sciences Center of Federal, University of Alagoas, Rio Largo, AL, Brazil
| | - Sonia S. Machado
- Tabuleiro do Martins, Institute of Federal University of Alagoas, Maceió-AL, Brazil
| | - Josealdo Tonholo
- Tabuleiro do Martins, Institute of Federal University of Alagoas, Maceió-AL, Brazil
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Barchanska H, Plonka J, Jaros A, Ostrowska A. Potential application of Pistia stratiotes for the phytoremediation of mesotrione and its degradation products from water. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2019; 21:1090-1097. [PMID: 31084361 DOI: 10.1080/15226514.2019.1606780] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The aim of the present work is to estimate remediation potential of Pistia stratiotes, its ability to uptake mesotrione (MES) - one of the most frequently used herbicides, and its main degradation products: 2-amino-4-methylsulfonyl benzoic acid (AMBA) and 4-methylsulfonyl-2-nitrobenzoic acid (MNBA). This research focuses on model experiments performed under laboratory conditions. The results show that Pistia stratiotes can uptake up to 75% of degradation products from 1 L of surface water samples polluted with 0.4 µg/L of each analyte during 7 days without significant phytotoxic effect. Under the same experimental conditions, the effectiveness of mesotrione sorption is in the range of 42-58%. The phytotoxicity of this compound is higher in comparison to its degradation products (decrease of chlorophyll concentration in plant tissues exposed to MES 27-32% vs 4-13% in case of exposition to AMBA and MNBA). The adequate nutrition of the plants is crucial to their well-being and thus the sorption of pollutants.
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Affiliation(s)
- Hanna Barchanska
- Department of Inorganic Chemistry, Analytical Chemistry and Electrochemistry, Faculty of Chemistry, Silesian University of Technology , Gliwice , Poland
| | - Joanna Plonka
- Department of Inorganic Chemistry, Analytical Chemistry and Electrochemistry, Faculty of Chemistry, Silesian University of Technology , Gliwice , Poland
| | - Angelika Jaros
- Department of Inorganic Chemistry, Analytical Chemistry and Electrochemistry, Faculty of Chemistry, Silesian University of Technology , Gliwice , Poland
| | - Angelika Ostrowska
- Department of Inorganic Chemistry, Analytical Chemistry and Electrochemistry, Faculty of Chemistry, Silesian University of Technology , Gliwice , Poland
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Li W, Xu X, Lyu B, Tang Y, Zhang Y, Chen F, Korshin G. Degradation of typical macrolide antibiotic roxithromycin by hydroxyl radical: kinetics, products, and toxicity assessment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:14570-14582. [PMID: 30877533 DOI: 10.1007/s11356-019-04713-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 02/25/2019] [Indexed: 06/09/2023]
Abstract
The degradation of roxithromycin (ROX) by hydroxyl radical (·OH) generated by UV/H2O2 was systematically investigated in terms of degradation kinetics, effects of water chemistry parameters, oxidation products, as well as toxicity evaluation. The degradation of ROX by UV/H2O2 with varying light irradiation intensity, initial ROX concentration, and H2O2 concentration in pure water and wastewater all followed pseudo-first-order kinetics. The second-order rate constant for reaction between ROX and ·OH is 5.68 ± 0.34 × 109/M/s. The degradation rate of ROX increased with the pH; for instance, the apparent degradation rates were 0.0162 and 0.0309/min for pH 4 and pH 9, respectively. The presence of natural organic matter (NOM) at its concentrations up to 10 mg C/L did not significantly affect the removal of ROX. NO3- and NO2- anions inhibited the degradation of ROX due to the consumption of ·OH in reactions with these ions. Fe3+, Cu2+, and Mg2+ cations inhibited the degradation of ROX, probably because of the formation of ROX-metal chelates. A total of ten degradation products were tentatively identified by HPLC/LTQ-Orbitrap XL MS, which mainly derived from the attack on the oxygen linking the lactone ring and the cladinose moiety, tertiary amine and oxime side chain moiety by ·OH. The toxicity evaluation revealed that UV/H2O2 treatment of ROX induced the toxicity to bioluminescent bacteria increased.
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Affiliation(s)
- Wei Li
- Co-Innovation center for sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Longpan Road 159, Nanjing, 210037, China.
| | - Xiujuan Xu
- Co-Innovation center for sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Longpan Road 159, Nanjing, 210037, China
| | - Baoling Lyu
- Co-Innovation center for sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Longpan Road 159, Nanjing, 210037, China
| | - Ying Tang
- Advanced Analysis and Testing Center, Nanjing Forestry University, Longpan Road 159, Nanjing, 210037, China
| | - Yinlong Zhang
- Co-Innovation center for sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Longpan Road 159, Nanjing, 210037, China.
| | - Fang Chen
- School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao, 066004, Hebei, China
| | - Gregory Korshin
- Department of Civil and Environmental Engineering, University of Washington, Box 352700, Seattle, WA, 98195-2700, USA
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Oxidative Degradation of Tannic Acid in Aqueous Solution by UV/S2O82− and UV/H2O2/Fe2+ Processes: A Comparative Study. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9010156] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Tannic acid (TA) is a major pollutant present in the wastewater generated from vegetable tanneries process and food processing. This work studied TA degradation by two advanced oxidation processes (APOs): UV irradiation at the wavelength of 254 nm in the presence of hydrogen peroxide (H2O2) and ferrous iron (photo-Fenton) and in the presence of potassium persulfate. The influence of certain experimental parameters such as K2S2O8, H2O2, Fe2+, and TA concentrations, initial pH and temperature was evaluated in order to obtain the highest efficiency in terms of aromatics (decay in UV absorbance at 276 nm) and TOC removals. Chemical oxidation of TA (0.1 mM) by UV/persulfate achieved 96.32% of aromatics removal and 54.41% of TOC removal under optimized conditions of pH = 9 and 53.10 mM of K2S2O8 after 60 min. The treatment of TA by photo-Fenton process successfully led to almost complete aromatics removal (99.32%) and high TOC removal (94.27%) from aqueous solutions containing 0.1 mM of TA at natural pH = 3 using 29.4 mM of H2O2 and 0.18 mM of Fe2+ at 25 °C after 120 min. More efficient degradation of TA by photo-Fenton process than UV/persulfate was obtained, which confirms that hydroxyl radicals are more powerful oxidants than sulfate radicals. The complete removal of organic pollution from natural waters can be accomplished by direct chemical oxidation via hydroxyl radicals generated from photocatalytic decomposition of H2O2.
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Degradation of Diallyl Phthalate (DAP) by Fenton Oxidation: Mechanistic and Kinetic Studies. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app9010023] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this work, the degradation and mineralization of Diallyl Phthalate (DAP) in water by Fenton oxidation was investigated. The effects of different experimental parameters including the initial pH, the hydrogen peroxide (H2O2) dose, the catalyst (Fe2+) dose, the iron source, and the DAP concentration on the rate and the yield of DAP degradation by Fenton oxidation were evaluated. DAP and its intermediates were quantified by high performance liquid chromatography (HPLC) analysis and the measurement of total organic carbon (TOC) during Fenton oxidation. The results obtained confirmed that hydroxyl radicals (HO•) generated from Fenton’s reaction were capable of completely eliminating DAP from water. Fenton oxidation of 100 mg/L DAP aqueous solution at pH = 3.2 required 1000 mg/L H2O2 and 50 mg/L Fe2+. Under these conditions, more than TOC removal exceeded 95% after 300 min Fenton oxidation. The competition kinetics method was used to determine an absolute rate constant of 7.26.109 M−1 s−1 for the reaction between DAP and HO• radicals. HPLC analysis showed that phthalic acid, 1,2-dihydroxybenzene, 1,2,4-trihydroxybenzene, maleic acid, formic acid and oxalic acid were the main intermediates formed during DAP degradation. Accordingly, a simple DAP degradation mechanism by the Fenton reaction was proposed. These promising results proved the potential of Fenton oxidation as a cost-effective method for the decontamination of wastewaters containing phthalates.
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Zhang A, Gu Z, Chen W, Li Q, Jiang G. Removal of refractory organic pollutants in reverse-osmosis concentrated leachate by Microwave-Fenton process. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:28907-28916. [PMID: 30105675 DOI: 10.1007/s11356-018-2900-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 08/02/2018] [Indexed: 06/08/2023]
Abstract
A microwave-Fenton technology was applied to dispose of the reverse-osmosis concentrated leachate. Influential factors on the treatment of concentrated leachate with the pure Fenton and microwave-Fenton method were investigated. For the conventional Fenton process, the removal efficiencies of chemical oxygen demand (CODCr), UV254, and the color number (CN) reached 84%, 87%, and 96%, respectively, with the biodegradability (BOD5/CODCr) increased from 0.13 to 0.51 at an initial pH of 5.0, Fe2+ of 0.04 mol/L, a n(H2O2)/n(Fe2+) ratio of 8 after a reaction time of 3 h. When incorporating the Fenton process with microwave irradiation, a comparative CODCr and UV254, and the CN removal rate of 75%, 83%, and 95%, and a high BOD5/CODCr of 0.62 were achieved under a microwave power of 390 W and an extremely shortened reaction time of only 8 min. Meanwhile, sludge quantity showed a reduction of 24.7%, decreased from 8.50 g/L to 6.40 g/L after the participation of microwave. In addition, molecular-weight fraction (MWF), UV-visible spectrum (UV-vis), and 3D-EEM spectrum tests demonstrated that the macromolecular and complex organic compounds in the wastewater were significantly decomposed into small molecular matters. Our results found that microwave-Fenton is a promising technology for concentrated leachate treatment, with much shorter reaction time, lower sludge production, and enhanced biodegradability, as well as comparative organic matter removal performance.
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Affiliation(s)
- Aiping Zhang
- Key Laboratory of Special Waste Water Treatment, Sichuan Province Higher Education System, Chemistry and Material Science of Sichuan Normal University, Chengdu, 610068, Sichuan Province, China.
| | - Zhepei Gu
- Key Laboratory of Special Waste Water Treatment, Sichuan Province Higher Education System, Chemistry and Material Science of Sichuan Normal University, Chengdu, 610068, Sichuan Province, China
| | - Weiming Chen
- Geosciences and Environmental Engineering of Southwest Jiaotong University, Chengdu, 611756, China
| | - Qibin Li
- Key Laboratory of Special Waste Water Treatment, Sichuan Province Higher Education System, Chemistry and Material Science of Sichuan Normal University, Chengdu, 610068, Sichuan Province, China
- Geosciences and Environmental Engineering of Southwest Jiaotong University, Chengdu, 611756, China
| | - Guobin Jiang
- Geosciences and Environmental Engineering of Southwest Jiaotong University, Chengdu, 611756, China
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Kamata M, Asami M, Matsui Y. Presence of the β-triketone herbicide tefuryltrione in drinking water sources and its degradation product in drinking waters. CHEMOSPHERE 2017; 178:333-339. [PMID: 28334673 DOI: 10.1016/j.chemosphere.2017.03.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 02/24/2017] [Accepted: 03/06/2017] [Indexed: 06/06/2023]
Abstract
Triketone herbicides are becoming popular because of their herbicidal activity against sulfonylurea-resistant weeds. Among these herbicides, tefuryltrione (TFT) is the first registered herbicide for rice farming, and recently its distribution has grown dramatically. In this study, we developed analytical methods for TFT and its degradation product 2-chloro-4-methylsulfonyl-3-[(tetrahydrofuran-2-yl-methoxy) methyl] benzoic acid (CMTBA). TFT was found frequently in surface waters in rice production areas at concentrations as high as 1.9 μg/L. The maximum observed concentration was lower than but close to 2 μg/L, which is the Japanese reference concentration of ambient water quality for pesticides. However, TFT was not found in any drinking waters even though the source waters were purified by conventional coagulation and filtration processes; this was due to chlorination, which transforms TFT to CMTBA. The conversion rate of TFT to CMBA on chlorination was almost 100%, and CMTBA was stable in the presence of chlorine. Moreover, CMTBA was found in drinking waters sampled from household water taps at a similar concentration to that of TFT in the source water of the water purification plant. Although the acceptable daily intake and the reference concentration of CMTBA are unknown, the highest concentration in drinking water exceeded 0.1 μg/L, which is the maximum allowable concentration for any individual pesticide and its relevant metabolites in the European Union Drinking Directive.
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Affiliation(s)
- Motoyuki Kamata
- College of Science and Engineering, Kanto Gakuin University, Mutsuura higashi 1-50-1, Kanazawa-ku, Yokohama, 236-8501, Japan.
| | - Mari Asami
- Department of Environmental Health, National Institute of Public Health, 2-3-6 Minami, Wako-shi, Saitama, 351-0197 Japan
| | - Yoshihiko Matsui
- Faculty of Engineering, Hokkaido University, N13W8, Sapporo, 060-8628, Japan
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11
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Dumas E, Giraudo M, Goujon E, Halma M, Knhili E, Stauffert M, Batisson I, Besse-Hoggan P, Bohatier J, Bouchard P, Celle-Jeanton H, Costa Gomes M, Delbac F, Forano C, Goupil P, Guix N, Husson P, Ledoigt G, Mallet C, Mousty C, Prévot V, Richard C, Sarraute S. Fate and ecotoxicological impact of new generation herbicides from the triketone family: An overview to assess the environmental risks. JOURNAL OF HAZARDOUS MATERIALS 2017; 325:136-156. [PMID: 27930998 DOI: 10.1016/j.jhazmat.2016.11.059] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 10/21/2016] [Accepted: 11/19/2016] [Indexed: 06/06/2023]
Abstract
Triketones, derived chemically from a natural phytotoxin (leptospermone), are a good example of allelochemicals as lead molecules for the development of new herbicides. Targeting a new and key enzyme involved in carotenoid biosynthesis, these latest-generation herbicides (sulcotrione, mesotrione and tembotrione) were designed to be eco-friendly and commercialized fifteen-twenty years ago. The mechanisms controlling their fate in different ecological niches as well as their toxicity and impact on different organisms or ecosystems are still under investigation. This review combines an overview of the results published in the literature on β-triketones and more specifically, on the commercially-available herbicides and includes new results obtained in our interdisciplinary study aiming to understand all the processes involved (i) in their transfer from the soil to the connected aquatic compartments, (ii) in their transformation by photochemical and biological mechanisms but also to evaluate (iii) the impacts of the parent molecules and their transformation products on various target and non-target organisms (aquatic microorganisms, plants, soil microbial communities). Analysis of all the data on the fate and impact of these molecules, used pure, as formulation or in cocktails, give an overall guide for the assessment of their environmental risks.
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Affiliation(s)
- E Dumas
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - M Giraudo
- Clermont Université, Université Blaise Pascal-Université d'Auvergne, Laboratoire Microorganismes: Génome et Environnement, BP 10448, 63000 Clermont Ferrand, France; CNRS, UMR 6023, LMGE, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - E Goujon
- Clermont Université, Université Blaise Pascal, Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier, 63000 Clermont-Ferrand, France; INRA, UMR PIAF 547, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - M Halma
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - E Knhili
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - M Stauffert
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France; Clermont Université, Université Blaise Pascal-Université d'Auvergne, Laboratoire Microorganismes: Génome et Environnement, BP 10448, 63000 Clermont Ferrand, France; CNRS, UMR 6023, LMGE, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - I Batisson
- Clermont Université, Université Blaise Pascal-Université d'Auvergne, Laboratoire Microorganismes: Génome et Environnement, BP 10448, 63000 Clermont Ferrand, France; CNRS, UMR 6023, LMGE, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - P Besse-Hoggan
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France.
| | - J Bohatier
- Clermont Université, Université Blaise Pascal-Université d'Auvergne, Laboratoire Microorganismes: Génome et Environnement, BP 10448, 63000 Clermont Ferrand, France; CNRS, UMR 6023, LMGE, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - P Bouchard
- Clermont Université, Université Blaise Pascal-Université d'Auvergne, Laboratoire Microorganismes: Génome et Environnement, BP 10448, 63000 Clermont Ferrand, France; CNRS, UMR 6023, LMGE, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - H Celle-Jeanton
- Clermont Université, Université Blaise Pascal, Laboratoire Magmas et Volcans, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6524, LMV, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - M Costa Gomes
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - F Delbac
- Clermont Université, Université Blaise Pascal-Université d'Auvergne, Laboratoire Microorganismes: Génome et Environnement, BP 10448, 63000 Clermont Ferrand, France; CNRS, UMR 6023, LMGE, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - C Forano
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - P Goupil
- Clermont Université, Université Blaise Pascal, Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier, 63000 Clermont-Ferrand, France; INRA, UMR PIAF 547, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - N Guix
- INRA, UMR 1095 Génétique, Diversité et Ecophysiologie des Céréales, 5 chemin de Beaulieu, 63039 Clermont-Ferrand, France; VetAgro Sup, 89 avenue de l'Europe, BP 35, 63370 Lempdes, France; UMR Génétique Diversité et Ecophysiologie des Céréales, INRA-UBP, UMR 1095, 63000 Clermont-Ferrand, France
| | - P Husson
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - G Ledoigt
- Clermont Université, Université Blaise Pascal, Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier, 63000 Clermont-Ferrand, France; INRA, UMR PIAF 547, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - C Mallet
- Clermont Université, Université Blaise Pascal-Université d'Auvergne, Laboratoire Microorganismes: Génome et Environnement, BP 10448, 63000 Clermont Ferrand, France; CNRS, UMR 6023, LMGE, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - C Mousty
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - V Prévot
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - C Richard
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France
| | - S Sarraute
- Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, 63000 Clermont-Ferrand, France; CNRS, UMR 6296, ICCF, TSA 60026, CS 60026, 63178 Aubière Cedex, France
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12
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Solís RR, Rivas FJ, Tierno M. Monopersulfate photocatalysis under 365 nm radiation. Direct oxidation and monopersulfate promoted photocatalysis of the herbicide tembotrione. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2016; 181:385-394. [PMID: 27393945 DOI: 10.1016/j.jenvman.2016.06.061] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 06/04/2016] [Accepted: 06/27/2016] [Indexed: 06/06/2023]
Abstract
Oxone(®) (potassium monopersulfate, MPS) has been used to oxidize the herbicide tembotrione in aqueous solution. Tembotrione elimination kinetics by MPS direct oxidation has been studied. The influence of the main operating variables affecting the process (MPS concentration, temperature and pH) has been evaluated. The process follows 2/3 and first orders in MPS and tembotrione concentrations, respectively. Optimal pH is located around circumneutral conditions. MPS decomposition in the presence of 365 nm UVA radiation and titanium dioxide has also been studied. A kinetic mechanism that simulates MPS decomposition has been proposed, showing the positive effect of titania load and MPS concentration. The system MPS/UVA/TiO2 significantly improves tembotrione and mineralization rate abatement if compared to runs conducted in the absence of MPS. Tembotrione total abatement was achieved in 20 min when 0.05 g L(-1) of titania and 10(-4) M of Oxone(®) were used. TOC conversion was roughly 70% in 90 min under similar operating conditions. An experimental design (Plackett-Burman) has been considered to study the influence of the main variables affecting tembotrione photocatalytic oxidation promoted by MPS.
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Affiliation(s)
- Rafael R Solís
- Department of Chemical Engineering and Physical Chemistry, University of Extremadura, Av. Elvas s/n, 06006, Badajoz, Spain; University Institute of Water Research, Climate Change and Sustainability, IACYS. University of Extremadura, Av. Elvas s/n, 06006, Badajoz, Spain.
| | - F Javier Rivas
- Department of Chemical Engineering and Physical Chemistry, University of Extremadura, Av. Elvas s/n, 06006, Badajoz, Spain; University Institute of Water Research, Climate Change and Sustainability, IACYS. University of Extremadura, Av. Elvas s/n, 06006, Badajoz, Spain
| | - Mercedes Tierno
- Department of Chemical Engineering and Physical Chemistry, University of Extremadura, Av. Elvas s/n, 06006, Badajoz, Spain
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Shi J, Yin D, Xu Z, Song D, Cao F. Fosfomycin removal and phosphorus recovery in a schorl/H2O2 system. RSC Adv 2016. [DOI: 10.1039/c6ra13637k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
More than 90% organic phosphorus could be removed by the Fenton-like oxidation, and about one-third inorganic phosphorus could be adsorbed and recovered on the schorl.
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Affiliation(s)
- Jing Shi
- School of Engineering
- China Pharmaceutical University
- Nanjing
- P. R. China
| | - Danyang Yin
- School of Environmental Science and Engineering
- Nanjing University of Information Science and Technology
- Nanjing 210044
- P. R. China
| | - Zhengwen Xu
- School of Environmental Science and Engineering
- Nanjing University of Information Science and Technology
- Nanjing 210044
- P. R. China
| | - Duanmei Song
- School of Engineering
- China Pharmaceutical University
- Nanjing
- P. R. China
| | - Feng Cao
- School of Engineering
- China Pharmaceutical University
- Nanjing
- P. R. China
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14
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Le Person A, Siampiringue M, Sarakha M, Moncomble A, Cornard JP. The photo-degradation of mesotrione, a triketone herbicide, in the presence of Cu II ions. J Photochem Photobiol A Chem 2016. [DOI: 10.1016/j.jphotochem.2015.09.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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15
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Chen T, Zhang Y, Yan J, Ding C, Yin C, Liu H. Heterogeneous photodegradation of mesotrione in nano α-Fe2O3/oxalate system under UV light irradiation. RSC Adv 2015. [DOI: 10.1039/c4ra11871e] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The application of a photo-Fenton-like system, consisting of nano α-Fe2O3/oxalate complex under UV light irradiation, to herbicide mesotrione was investigated.
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Affiliation(s)
- Tianming Chen
- School of Environment Science and Spatial Information of China
- University of Mining and Technology
- Xuzhou 221008
- China
- School of Environmental Science and Engineering
| | - Yanqiu Zhang
- School of Environment Science and Spatial Information of China
- University of Mining and Technology
- Xuzhou 221008
- China
| | - Jinlong Yan
- School of Environmental Science and Engineering
- Yancheng Institute of Technology
- Yancheng 224051
- China
| | - Cheng Ding
- School of Environmental Science and Engineering
- Yancheng Institute of Technology
- Yancheng 224051
- China
| | - Chuntao Yin
- School of Environmental Science and Engineering
- Yancheng Institute of Technology
- Yancheng 224051
- China
| | - Hui Liu
- School of Environmental Science and Engineering
- Yancheng Institute of Technology
- Yancheng 224051
- China
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16
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Ahmed MM, Brienza M, Goetz V, Chiron S. Solar photo-Fenton using peroxymonosulfate for organic micropollutants removal from domestic wastewater: comparison with heterogeneous TiO₂ photocatalysis. CHEMOSPHERE 2014; 117:256-261. [PMID: 25108605 DOI: 10.1016/j.chemosphere.2014.07.046] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 07/15/2014] [Accepted: 07/15/2014] [Indexed: 06/03/2023]
Abstract
This work aims at decontaminating biologically treated domestic wastewater effluents from organic micropollutants by sulfate radical based (SO4(-)) homogeneous photo-Fenton involving peroxymonosulfate as an oxidant, ferrous iron (Fe(II)) as a catalyst and simulated solar irradiation as a light source. This oxidative system was evaluated by using several probe compounds belonging to pesticides (bifenthrin, mesotrione and clothianidin) and pharmaceuticals (diclofenac, sulfamethoxazole and carbamazepine) classes and its kinetic efficiency was compared to that to the well known UV-Vis/TiO2 heterogeneous photocatalysis. Except for carbamazepine, apparent kinetic rate constants were always 10 times higher in PMS/Fe(II)/UV-Vis than in TiO2/UV-Vis system and more than 70% of total organic carbon abatement was reached in less than one hour treatment. Hydroxyl radical (OH) and SO4(-) reactivity was investigated using mesotrione as a probe compound through by-products identification by liquid chromatography-high resolution-mass spectrometry and transformation pathways elucidation. In addition to two OH based transformation pathways, a specific SO4(-) transformation pathway which first involved degradation through one electron transfer oxidation processes followed by decarboxylation were probably responsible for mesotrione degradation kinetic improvement upon UV-Vis/PMS/Fe(II) system in comparison to UVVis/TiO2 system.
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Affiliation(s)
- Moussa Mahdi Ahmed
- UMR HydroSciences 5569, Montpellier Université, 15 Avenue Ch. Flahault, 34093 Montpellier cedex 5, France.
| | - Monica Brienza
- PROMES-CNRS, UPR 8521, Tecnosud, Rambla de la Thermodynamique, 66100 Perpignan, France
| | - Vincent Goetz
- PROMES-CNRS, UPR 8521, Tecnosud, Rambla de la Thermodynamique, 66100 Perpignan, France
| | - Serge Chiron
- UMR HydroSciences 5569, Montpellier Université, 15 Avenue Ch. Flahault, 34093 Montpellier cedex 5, France
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17
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Kinetics and the mechanism of the photocatalytic degradation of mesotrione in aqueous suspension and toxicity of its degradation mixtures. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.molcata.2014.04.033] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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18
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Dbira S, Bedoui A, Bensalah N. Investigations on the Degradation of Triazine Herbicides in Water by Photo-Fenton Process. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/ajac.2014.58059] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Jović M, Manojlović D, Stanković D, Dojčinović B, Obradović B, Gašić U, Roglić G. Degradation of triketone herbicides, mesotrione and sulcotrione, using advanced oxidation processes. JOURNAL OF HAZARDOUS MATERIALS 2013; 260:1092-9. [PMID: 23892174 DOI: 10.1016/j.jhazmat.2013.06.073] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 06/14/2013] [Accepted: 06/30/2013] [Indexed: 05/26/2023]
Abstract
Degradation of two triketone herbicides, mesotrione and sulcotrione, was studied using four different advanced oxidation processes (AOPs): ozonization, dielectric barrier discharge (DBD reactor), photocatalysis and Fenton reagent, in order to find differences in mechanism of degradation. Degradation products were identified by high performance liquid chromatography (HPLC-DAD) and UHPLC-Orbitrap-MS analyses. A simple mechanism of degradation for different AOP was proposed. Thirteen products were identified during all degradations for both pesticides. It was assumed that the oxidation mechanisms in the all four technologies were not based only on the production and use of the hydroxyl radical, but they also included other kinds of oxidation mechanisms specific for each technology. Similarity was observed between degradation mechanism of ozonation and DBD. The greatest difference in the products was found in Fenton degradation which included the opening of benzene ring. When degraded with same AOP pesticides gave at the end of treatment the same products. Global toxicity and COD value of samples was determined after all degradations. Real water sample was used to study influence of organic matter on pesticide degradation. These results could lead to accurate estimates of the overall effects of triketone herbicides on environmental ecosystems and also contributed to the development of improved removal processes.
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Affiliation(s)
- Milica Jović
- Innovation Center of the Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia.
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Qin J, Li H, Lin C, Chen G. Can rainwater induce Fenton-driven degradation of herbicides in natural waters? CHEMOSPHERE 2013; 92:1048-52. [PMID: 23545190 DOI: 10.1016/j.chemosphere.2013.03.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Revised: 02/22/2013] [Accepted: 03/04/2013] [Indexed: 06/02/2023]
Abstract
Microcosm experiments were conducted to examine Fenton reaction-driven degradation of three common herbicides exposed to a variety of Fe(2+)-H2O2 combinations that are likely to be encountered in natural water environments. The results show that these combinations had significant (P<0.05) effects on removing the water-borne herbicides. This discovery sheds some light on the possible role of rainwater-borne H2O2 in inducing Fenton reaction in many natural waters such as lakes, streams, estuaries and tidal zones, fishponds and paddy fields that may contain ferrous ion at micromolar levels. The research findings obtained from this preliminary work provide a rationale for undertaking further study to confirm the presence of an overlooked naturally-occurring process that may lead to rapid dissipation of many herbicides and other organic pollutants in open water environments. Our immediate follow-up work is to continue the laboratory-scale investigations under more complex experimental conditions, including the uses of various natural water samples for the experiments. This will provide a basis for future field-based study.
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Affiliation(s)
- Junhao Qin
- Institute of Tropical and Subtropical Ecology, South China Agricultural University, Guangzhou 510642, China
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Murati M, Oturan N, Aaron JJ, Dirany A, Tassin B, Zdravkovski Z, Oturan MA. Degradation and mineralization of sulcotrione and mesotrione in aqueous medium by the electro-Fenton process: a kinetic study. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2012; 19:1563-1573. [PMID: 22116735 DOI: 10.1007/s11356-011-0667-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Accepted: 11/11/2011] [Indexed: 05/31/2023]
Abstract
INTRODUCTION The degradation and mineralization of two triketone (TRK) herbicides, including sulcotrione and mesotrione, by the electro-Fenton process (electro-Fenton using Pt anode (EF-Pt), electro-Fenton with BDD anode (EF-BDD) and anodic oxidation with BDD anode) were investigated in acidic aqueous medium. METHODS The reactivity of both herbicides toward hydroxyl radicals was found to depend on the electron-withdrawing effect of the aromatic chlorine or nitro substituents. The degradation of sulcotrione and mesotrione obeyed apparent first-order reaction kinetics, and their absolute rate constants with hydroxyl radicals at pH 3.0 were determined by the competitive kinetics method. RESULTS AND DISCUSSION The hydroxylation absolute rate constant (k(abs)) values of both TRK herbicides ranged from 8.20 × 10(8) (sulcotrione) to 1.01 × 10(9) (mesotrione) L mol(-1) s(-1), whereas those of the TRK main cyclic or aromatic by-products, namely cyclohexane 1,3-dione, (2-chloro-4-methylsulphonyl) benzoic acid and 4-(methylsulphonyl)-2-nitrobenzoic acid, comprised between 5.90 × 10(8) and 3.29 × 10(9) L mol(-1) s(-1). The efficiency of mineralization of aqueous solutions of both TRK herbicides was evaluated in terms of total organic carbon removal. Mineralization yields of about 97-98% were reached in optimal conditions for a 6-h electro-Fenton treatment time. CONCLUSIONS The mineralization process steps involved the oxidative opening of the aromatic or cyclic TRK by-products, leading to the formation of short-chain carboxylic acids, and, then, of carbon dioxide and inorganic ions.
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Affiliation(s)
- Minir Murati
- Laboratoire Géomatériaux et Environnement, Université Paris-Est, Marne-La-Vallée, France
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